I would try to convince her to 'uninsist'. That seems to blend into its site in its earthy color. A plus to my eye - And I am also in the PNW. She needs landscaping. My own ground here on the coast is too wet for spading and preparing new beds in January. And please note that the house behind and to the left are white. This house also white would be redundant.

White or black as in the Decoist example.

Yes, Villa Grey looks very Celery on the wall (I have it in a bedroom, North & East light) I would go with SW Alabaster. a warm white that will look whiter in the light and warm, not yellow in the north light. (not to mention, it goes well with darker colors, so if you plan to do a dark accent somewhere, it's very soft. That red wall would look nice SW Naval (a deep clean Navy) Personally, I would paint the ceiling and all the woodwork SW Alabaster for a fresh look, and to open up the space.

I would do black. As to sheen, that is up to you. Some (apparently your contractor does), like a high glass enamel. I would prefer semi gloss enamel, myself, and I have a few neighbors that use a lot of black, and they prefer satin. Its all individual taste. Which sheen do you like?